Angled dental platform assembly and methods

ABSTRACT

A dental implant system includes a base member that is adapted to be embedded within a patient&#39;s jawbone at a treatment site. The base member has a generally flat top defining an outer periphery, a buccal side, a lingual side, a bottom, and a central opening. The lingual side or the buccal side is longer than the other. The base member is configured to be positioned within a recess in the patient&#39;s jawbone. An implant screw includes a head and a threaded end. The threaded end is adapted to pass through the central opening of the base member and into the patient&#39;s jawbone, and the head is adapted to be seated within the central opening of the base member after the threaded end is screwed into the patient&#39;s jawbone. An abutment is configured to be placed onto the top of the base member.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation-in-part application of copending U.S.application Ser. No. 13/014,526, filed Jan. 26, 2011, which is acontinuation-in-part application of copending U.S. application Ser. No.12/694,911 filed Jan. 27, 2010 which is a continuation-in-part ofcopending U.S. application Ser. No. 12/243,676, filed Oct. 1, 2008 whichis a continuation-in-part application of co-pending U.S. applicationSer. No. 12/074,524 filed on Mar. 4, 2008. The complete disclosures ofeach of these applications are herein incorporated by reference.

BACKGROUND OF THE INVENTION

Implants are popular means of replacing a lost tooth. Due to theirrelatively low maintenance and durability people often prefer implantsto bridges. Nevertheless, there is a largely undocumented body ofcomplaints voiced to front line dentists about implants, by theirpatients. These complaints generally are about food impacting andaccumulating around and beneath the crown portion of the implant in theenlarged periodontal gap between the implant and the adjacent teeth.

BRIEF SUMMARY OF THE INVENTION

The invention describes various dental implant systems as well asmethods for securing such systems within a patient's jaw. According toone embodiment, a method for securing a dental implant system to apatient's jawbone proceeds by removing a portion of the patient's gum ata treatment site sufficient to expose the patient's jawbone. Also, aportion of the patient's jawbone is removed at the treatment site toform a recess. The recess tapers downward in a direction from lingual tobuccal or from buccal to lingual. A base member is positioned at thetreatment site such that the base member is embedded within the recess.The base member has a top defined by an outer periphery, a bottom, abuccal side, a lingual side, and a tapered central opening. The lingualside or the buccal side is longer than the other depending on how therecess in the patient's jawbone tapers. The base member is positionedsuch that buccal side is buccal on the jawbone and the lingual side islingual on the jawbone. Also, a drill bit is placed through the centralopening and a hole is drilled in the jawbone. An implant screw isinserted through the central opening. The implant screw has a head witha tapered section and a threaded end. The implant screw is turned tosecure the threaded end within the hole in the jawbone and to seat thehead of the implant screw within the tapered opening of the base member.

In one specific aspect, the top has a planar top surface that isdisposed at an angle relative to a planar bottom surface of the bottom.The angle of the top surface relative to the bottom surface serves toraise the buccal side of the base member relative to the lingual side ofthe base member (or vice versa) when the base member is secured withinthe recess. Typically, the top of the base member is positioned so as tobe generally flush with the patient's jawbone.

In another aspect, an abutment is placed onto the top surface of thebase member. The abutment has a buccal side and a lingual side, and oneof the lingual side and the buccal side is longer than the other.Further, the lingual side of the abutment is aligned with the lingualside of the base member. The abutment may be non-rotatably mounted tothe base member in a variety of ways. As one specific example, the topof the base member may include at least one recess where a locating pinis placed. The pin is also placed into a corresponding recess on theabutment.

In a further aspect, the implant screw includes a threaded hole forreceiving a capture screw. Also, a healing cover may be placed onto thebase member and the patient's gun sutured over the healing cover. Thehealing cover extends to the outer perimeter of the base member. Aftertime, the healing cover is removed from the base member and an abutmentis attached to the base using a capture screw that extends through theabutment and into the implant screw. Further, a crown may be to theabutment.

In another embodiment, the invention provides a dental implant systemthat comprises a base member that is adapted to be embedded within apatient's jawbone at a treatment site. The base member has a generallyflat top defining an outer periphery, a buccal side, a lingual side, abottom, and a central opening. The base member is configured to bepositioned within a recess in the patient's jawbone, and one of thelingual side and the buccal side is longer than the other depending onthe state of the jawbone at the treatment site. The system furtherincludes an implant screw comprising a head and a threaded end. Thethreaded end is adapted to pass through the central opening of the basemember and into the patient's jawbone. The head is adapted to be seatedwithin the central opening of the base member after the threaded end isscrewed into the patient's jawbone. Further, the implant screw defines athreaded opening in the head. The system also includes an abutment thatis configured to be placed onto the top of the base member. The abutmenthas a bottom surface that is configured to be positioned adjacent thebase member, and a shaped upper surface that is adapted to receive acrown.

In one aspect, the abutment has a buccal side and a lingual side, andone of the lingual side and the buccal side is longer than the other.The abutment may also have a flat upper portion, and a flat bottomsurface is disposed at an angle relative to the flat upper portion.

In some cases, the top of the base member has a planar top surface thatis disposed at an angle relative to a planar bottom surface of thebottom. The angle of the planar top surface relative to the planarbottom surface of the bottom side is in the range from about 5 degreesto about 20 degrees. Further, the bottom of the abutment may have anouter perimeter that generally matches the outer periphery of the basemember.

In one optional aspect, the system further includes a through holeextending longitudinally through the abutment. A locating member extendsfrom the through hole of the abutment and into the head of the implantscrew. At least one alignment feature is configured to align the basemember with the abutment. Further, a capture screw is configured to beinserted through the through hole of the abutment, through the locatingmember and into the threaded opening in the head of the implant screw.

In a further optional aspect, the base member defines at least onerecess in the top. The bottom of the abutment defines at least onerecess that is aligned with the recess in the base member when theabutment is placed onto the base member. The alignment feature comprisesa pin that is configured to fit within the recess of the base member andthe abutment. The abutment and the base member each include anotherrecess that are aligned with each other when the abutment is placed ontothe base member.

In some cases, the central opening is tapered, and the implant screw hasa tapered head section to seat within the tapered central opening. Inanother feature, the outer periphery of the base member includes acoating or surface treatment to increase the surface area of the outerperiphery to promote osseointegration. Further, a crown is adapted to bemounted to the abutment.

In yet a further embodiment, the invention provides a platform forsecuring a dental crown to a patient's jawbone. The platform comprises abase member that is adapted to be embedded within a patient's jawbone ata treatment site. The base member has a generally flat top side, agenerally flat bottom side, an outer periphery, and a central openingthat tapers inward with a constant taper from the top surface to thebottom surface and is configured to receive an implant screw. The topside has a top surface that is disposed at an angle relative to a bottomsurface of the bottom side.

In still a further embodiment, a dental implant system comprises anintegral base member/abutment having an upper portion and a lowerportion. The upper portion is shaped to receive a crown, and the lowerportion is adapted to be at least partially embedded within a recess ina patient's jawbone at a treatment site. A central opening extendsthrough the base member/abutment. The system as includes an implantscrew that comprises a head and a threaded end. The threaded end isadapted to pass through the central opening and into the patient'sjawbone, and the head is adapted to be seated within the central openingof the base member/abutment after the threaded end is screwed into thepatient's jawbone.

In another embodiment, a method for securing a dental implant system toa patient's jawbone includes the step of removing a portion of thepatient's gum at a treatment site sufficient to expose the patient'sjawbone. A portion of the patient's jawbone at the treatment site isalso removed to form a recess. This recess preferably has a shape andsize similar to a base member that will subsequently be placed into therecess. This base member has a generally flat top side defined by anouter perimeter and a tapered central opening. The base member ispositioned in the recess, typically with the top side being flush with atop surface of the jawbone. A drill bit is placed through the centralopening and a hole is drilled in the jawbone. An implant screw isinserted through the central opening. This implant screw has a head witha tapered section and a threaded end. The implant screw is turned tosecure the threaded end within the hole in the jawbone and to seat thehead of the implant screw within the tapered opening of the base member.

In some cases drill bits of increasing size may be inserted into thecentral opening to progressively expand the size of the hole in thejawbone. In one particular aspect, the base member is generallyrectangular in geometry as is the recess in the jawbone.

With the base member secured, an abutment is placed onto the top surfaceof the base member. To help prevent rotation of the abutment relative tothe base member, the top side of the base member may include at leastone recess and a locating pin that is placed in the recess. The locatingpin is inserted into a corresponding recess on the abutment when placingthe abutment onto the base member.

In one aspect, the implant screw includes a threaded hole. In this way,a capture screw may be inserted through a central opening of theabutment and into the threaded hole to secure the abutment to the basemember. Further, the implant screw may be seated into the jawbone usinga torque wrench using a force of at least about 35 Ncm.

The abutment may include a locating sleeve extending from the centralopening of the abutment. The locating sleeve may be placed into thecentral opening of the base member to help position the abutment on thebase member.

Prior to placement of the abutment, a healing cover may be placed ontothe base member and the patient's gun sutured over the healing cover.The healing cover in one aspect extends to the outer perimeter of thebase member. After the site as healed, the healing cover is accessed andremoved from the base member. A tissue contouring cap may then be placedonto the base member using a screw that extends into the implant screw.This helps to form the surgical site area and prepare it for receivingthe crown. After the tissue has properly formed, the healing cover isremoved and the abutment is secured to the base using a capture screwthat extends through the abutment and into the implant screw. Further, acrown is attached to the abutment.

In one particular aspect, the base member has a generally flat bottomside, and the central opening tapers inward from the top surface to thebottom surface with a constant taper. Also, the base member has an outerperiphery that tapers with a straight taper inward from the top surfaceto the bottom surface such that the top surface is greater in surfacearea than the bottom surface. Further, the outer periphery of the basemember may be roughened.

The invention further provides a dental implant system that comprises abase member that is adapted to be embedded within a patient's jawbone ata treatment site. The base member has a generally flat top side definingan outer periphery, a bottom side, and a central opening. At least onerecess is included in the top side for receiving an alignment pin. Thesystem further includes an implant screw that comprises a head and athreaded end. The threaded end is adapted to pass through the centralopening of the base member and into the patient's jawbone. Also, thehead is adapted to be seated within the central opening of the basemember after the threaded end is screwed into the patient's jawbone. Theimplant screw further includes a threaded opening in the head.

The system may further include an abutment that is configured to beplaced onto the top side of the base member so that a crown may beplaced on the abutment. The abutment comprises a flat bottom surfacethat is configured to be positioned adjacent the top side of the basemember. The bottom surface of the abutment has an outer perimeter thatgenerally matches the outer periphery of the base member. The bottomsurface defines at least one recess that is aligned with the recess inthe base member when the abutment is placed onto the base member. Theabutment further includes a shaped upper surface that is adapted toreceive a crown and a through hole extending longitudinally through theabutment.

In some cases, a locating sleeve may extend from the through hole of theabutment and into the head of the implant screw. Also, an alignment pinmay be placed within the recess of the base member and the abutment.Further, a capture screw may be inserted through the through hole of theabutment, through the locating sleeve and into the threaded opening inthe head of the implant screw.

In one aspect, the abutment and the base member each include a secondset of recesses. These recesses are aligned with each other when theabutment is placed onto the base member. Another alignment pin is placedwithin the second set of recesses. In a further aspect, the sleeve iscylindrical in geometry, and the capture screw has an upper end with asmooth outer surface that is configured to fit within the sleeve.

In one particular aspect, the central opening is tapered, and theimplant screw has a tapered head section to seat within the taperedcentral opening. Also, the base member may be generally rectangular ingeometry. Further, the outer periphery of the base member may taperinward from the top surface to the bottom surface such that the topsurface is greater in surface area than the bottom surface. The outerperiphery of the base member may be roughened.

In yet a further embodiment, the invention provides a platform forsecuring a dental crown to a patient's jawbone. The platform comprises abase member that is adapted to be embedded within a patient's jawbone ata treatment site. The base member has a generally flat top side, agenerally flat bottom side, an outer periphery, and a central openingthat tapers inward with a constant taper from the top surface to thebottom surface and is configured to receive an implant screw. The topside further includes a pair of recesses that are adapted to receivealignment pins that are configured to be received within correspondingrecesses of an abutment to ensure non-rotatable alignment of theabutment with the base member.

In one particular embodiment, the invention further provides anexemplary method for securing a dental implant (or implant screw) to apatient's jawbone. According to the method, a portion of the patient'sgum is removed sufficient to expose the patient's jawbone. This may bedone after the patient's tooth or other dental work has been removed.Also, a portion of the patient's jawbone is removed. The depth of boneremoval may be in the range from about 1 mm to about 4 mm. A base memberis positioned at the treatment site such that it is embedded within thepatient's jawbone wherein the bone has been removed. The base member mayhave a generally flat top side defined by an outer perimeter, a taperedcentral opening and at least one screw hole that is positioned betweenthe central opening and the outer perimeter. A small securing screw isplaced through the screw hole and rotated until it is screwed into thepatient's jawbone and a head of the securing screw is at least flushwith the top side of the base member. In this way, the base member isembedded within and securely fastened to the patient's jawbone. Thisbase member will subsequently serve as a stable platform for aprosthesis. An implant screw is placed through the central opening ofthe base member. The implant screw has a head with a tapered section anda threaded end. The implant screw is turned to secure the threaded endwithin the jawbone and to seat the head of the implant screw within thetapered opening of the base member. Once the implant screw is secured tothe jawbone and appropriate healing has occurred, a prosthesis, such asa crown, may be coupled to the implant screw.

In one aspect, the base member includes two screw holes that arepositioned between the outer periphery and the central opening. As oneexample, the base member may be generally rectangular in geometry, withthe two screw holes being located in corners of the base member. Thisserves to further secure the base member to the patient's jawbone. Also,when the base member is rectangular, the surgeon may also surgicallyremove a rectangular section of the jawbone so that the base member willfit within the resulting depression in the jawbone.

In another aspect, the top side of the base member may be embeddedwithin the jawbone such that it is generally flush with the top surfaceof the patient's jawbone. In a further aspect, the top side may furtherinclude at least one matable feature that is configured to mate with acorresponding feature on a crown to ensure non-rotatable alignment ofthe crown with the base member. The implant screw may further include athreaded hole and the crown may include a bolt so that the bolt may bescrewed into the threaded hole.

In yet another aspect, the base member may have a generally flat bottomside, and the central opening may taper inward from the top surface tothe bottom surface with a constant taper. Further, the base member mayhave an outer periphery that tapers with a straight taper inward fromthe top surface to the bottom surface such that the top surface isgreater in surface area than the bottom surface.

In some cases, the outer periphery of the base member may be roughenedto increase the surface area of the base member. This in turn serves toenhance bone growth to the base member.

In another embodiment, the invention provides a dental implant systemthat comprises a base member that is adapted to be embedded within apatient's jawbone at a treatment site. The base member has a generallyflat top side defining an outer periphery, a bottom side, a centralopening, and at least one screw hole positioned between the centralopening and the outer periphery. The system also includes an implantscrew that comprises a head and a threaded end that is adapted to passthrough the central opening of the base member and into the patient'sjawbone. The head of the implant screw is adapted to be seated withinthe central opening of the base member after the threaded end is screwedinto the patient's jawbone. The system further includes a securing screwthat is smaller in size than the implant screw and has a head and athreaded end. The threaded end of the securing screw passes through thescrew hole of the base member and into the patient's jawbone. In thisway, the securing screw may be used to help further secure the basemember to the patient's jawbone. In turn, this helps to stabilize theimplant screw and the prosthesis that will be coupled to the implantscrew.

In one aspect, the central opening is tapered and has a beveled edge.Also, the implant screw has a tapered head section to seat within thetapered central opening. This particular configuration is also useful inpreventing microleakage between the base member and the implant screw.

In another aspect, the base member is generally rectangular in geometry,and the securing hole is located in a corner of the base member. In oneparticularly useful arrangement, the base member has two securing holesfor use with two securing screws. The securing holes are located inopposing corners of the base member. Also, the securing holes may have atapered section and the heads of the securing screws may have a taperedsection. Further, the securing screws may each have a pointed end and adiameter of about 1.5 mm.

In a further aspect, the base member includes a plurality of retentiongrooves that are located on the outer periphery. Also, the outerperiphery of the base member may tapers inward from the top surface tothe bottom surface such that the top surface is greater in surface areathan the bottom surface. With this arrangement, the taper may beginbelow retention grooves. Additionally, the outer periphery of the basemember is roughened to facilitate bone growth.

The system may be used with various prosthesis. For example, a crown maybe mounted to the head of the implant screw. In some cases, the top sideof the base member may includes at least one matable feature, and thecrown may also include a corresponding matable feature that mates withthe feature on the base member to non-rotationally secure the crown tothe base member. The implant screw may include a threaded hole and thecrown may include a bolt so that the bolt may be screwed into thethreaded hole.

In yet another embodiment, the invention provides a platform forsecuring a dental crown to a patient's jawbone. The platform comprises abase member that is adapted to be embedded within a patient's jawbone ata treatment site. The base member has a generally flat top side, agenerally flat bottom side, an outer periphery, a central opening and ascrew hole positioned between the central opening and the outerperiphery. The central opening tapers inward with a constant taper fromthe top surface to the bottom surface and is configured to receive animplant screw. The top side may further include at least one matablefeature that is configured to mate with a corresponding feature on acrown to ensure non-rotatable alignment of the crown with the basemember.

In one aspect, the outer periphery may include a plurality of retentiongrooves, and the outer periphery may taper with a straight taper inwardfrom the retention grooves to the bottom surface such that the topsurface is greater in surface area than the bottom surface. In anotheraspect, the base member may be generally rectangular in geometry, andthe securing hole is located in a corner of the base member. Two or moresecuring holes and securing screws may also be used.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation diagram of an implant having an enlarged baseseated directly on the jaw.

FIG. 2 is an exploded view of the base plate and crown supporting meansof the implant.

FIGS. 3-7 illustrate an embodiment of steps in a method for installingthe tooth implant of FIG. 1.

FIG. 8 is a top perspective view of one embodiment of a platform or baseaccording to the invention.

FIG. 9 is a bottom perspective view of the base of FIG. 8.

FIG. 10 illustrates a cross-sectional side view of a patient's jawbonethat has been drilled to receive an implant and in which a rectangularportion has been surgically removed in order to receive a base accordingto the invention.

FIG. 11 illustrates an implant that has been inserted into the jawboneof FIG. 10 with a corresponding base and abutment.

FIG. 12 is a top view of the base and implant of FIG. 11 prior toattachment of the abutment.

FIG. 13 is a perspective view of a template that may be employed whensurgically removing portions of the patient's jawbone according to theinvention.

FIG. 14 illustrates the surgical recesses formed within the patient'sjawbone using the template of FIG. 13.

FIG. 15 illustrates crowns that have been restored to the surgical sitesof FIG. 14 according to the invention.

FIG. 16 illustrates a side view of one particular embodiment of a dentalimplant system according to the invention.

FIG. 17 is an exploded view of the dental implant system of FIG. 16.

FIG. 18 is a cross sectional view of the dental implant system of FIG.19 taken along lines 18-18.

FIG. 19 is a cross sectional view of the dental implant system of FIG.16 taken along lines 19-19.

FIG. 20 illustrates a portion of a patient's jawbone where a tooth hasbeen removed.

FIG. 21 illustrates the portion of the patient's jawbone of FIG. 20 witha portion of the jawbone removed to form a recess.

FIG. 22 illustrates the jawbone of FIG. 21 with a base member orplatform inserted into the recess.

FIG. 23 illustrates a drill passing through the base member that is usedto create a hole in the patient's jawbone.

FIG. 24 illustrates an implant screw that has been inserted into thehole of FIG. 23.

FIG. 25 illustrates a healing cap that has been placed onto the basemember after insertion of the implant screw.

FIG. 26 illustrates a tissue contouring cap that has been placed ontothe base member after removal of the healing cap.

FIG. 27 illustrates the attachment of an abutment to the base member.

FIG. 28 illustrates the attachment of a crown to the abutment of FIG.27.

FIG. 29 is a top perspective view of a further embodiment of a dentalimplant system according to the invention.

FIG. 30 is an exploded side view of the dental implant system of FIG.29.

FIG. 31 illustrates a patient's jawbone where a tooth has been removed,with the patient's jawbone angling from lingual to buccal.

FIG. 32 is a partial cross sectional side view of the jawbone of FIG. 31where the tooth is missing.

FIG. 33 illustrates the portion of the patient's jawbone of FIG. 32 witha portion of the jawbone removed to form a recess.

FIG. 34 illustrates the jawbone of FIG. 33 with a base member orplatform inserted into the recess.

FIG. 35 illustrates a drill passing through the base member that is usedto create a hole in the patient's jawbone.

FIG. 36 illustrates an implant screw that has been inserted into thehole of FIG. 35.

FIG. 37 illustrates a healing cap that has been placed onto the basemember after insertion of the implant screw.

FIG. 38 illustrates a tissue contouring cap that has been placed ontothe base member after removal of the healing cap.

FIG. 39 illustrates the attachment of an abutment to the base member.

FIG. 40 illustrates the attachment of a crown to the abutment of FIG.39.

FIG. 41 illustrates a further embodiment of a dental implant system.

FIG. 42 is a cross sectional side view of the implant system of FIG. 41when implanted in a patient's jawbone.

The following is a discussion and description of specific embodiments ofthis invention, such being made with reference to the drawings, whereinthe same reference numerals are used to indicate the same or similarparts and/or structure. It should be noted that such discussion anddescription is not meant to unduly limit the scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Restoring the edentulous space of missing first and second molars andbicuspids can be problematic. This is because these teeth are typicallysquare or rectangular in geometry. Typical dental procedures restorethis space using round dental implants. When the crown is placed ontothe implant, there are excessive voids between the crown and adjacentteeth. These spaces serve as food traps and will eventually lead totooth decay of the adjacent teeth. This problem generally arises becausethe implant is round yet is trying to fill a generally square orrectangular space.

One important feature of the invention is a way to provide a platformthat generally fills this edentulous space so that when a square orrectangular crown is placed onto the implant there is minimal spacebetween the crown and the adjacent teeth. The platforms of the inventionare generally square or rectangular and are positioned about the implantto provide a convenient surface to attach the crown. In some cases, partof the patient's jawbone may be removed so that the platform may becountersunk within the patient's jawbone. In this way, when the crown isplaced onto the platform not only will it be generally aligned with theadjacent teeth but the jawbone will tend to grow about the platform toprovide a stable surface to support the crown.

A wide variety of platforms may be used in connection with mostcommercially available implants. Typically, the outer periphery of theplatform will be generally rectangular or square and will have a centralopening through which the implant may be inserted. The top surface ofthe platform is typically flat in geometry. However, it may include oneor more detents or other features to mate with a corresponding featureon the crown and/or abutment so as to prevent rotation of the crownrelative to the platform. Also, the platform may have one or more holesto permit small surgical screws to be inserted through the platform andinto the jawbone so that the platform may be further secured to thepatient's jawbone. These holes may be countersunk so that the surgicalscrews are generally flush with the top surface of the platform. Theouter and bottom surfaces of the platform may have various grooves orroughened surfaces to facilitate bone healing and bone grown to theplatform.

Once the platform is securely in place it essentially converts the roundimplant into a square or rectangular implant so as the match the outergeometry of the crown. In this way, voids or spaces between adjacentteeth are minimized to prevent decay and tooth loss that may otherwiseresult from the placement of the implant and crown.

FIG. 1 is a side elevation diagram of an improved tooth implant assembly20 having a base 24 for seating on jaw 16. In one embodiment, toothimplant assembly 20 includes base plate 24, a base attachment fastener28 (also referred to as an implant screw or simply an implant), a crownattachment fastener 34, a crown supporting mechanism 36 (FIG. 2), and atooth crown 38.

Generally, the tooth implant assembly 20 comprises: i) a crown portion22 having a lower portion 23 adapted for seating and connection; ii)base 24 having an upper portion adapted to matably receive the crownportion 22, a lower portion adapted to seat directly on (or be embeddedwithin) the bone 14 of one of the jaws 16, the base 24 having anupright, or central, opening 26 therethrough; and, iii) a baseattachment fastener 28 having a head 29 adapted to be seated o andaround upright opening 26, and a threaded end portion, or shaft, 30 forscrewable reception in the jaw 16 to thereby anchor the base 24 thereon.The base 24 of the implant 20 is enlarged to better distribute load onthe jaw 16 and thereby additionally allow said crown portion 22 to havemore upright peripheral sidewalls 31, so that embrasures, or periodontalgaps, 12 (FIGS. 3-7) between the bottom portion of the crown portion andadjacent teeth 10 (FIGS. 3-7) are thereby substantially reduced, and sothat both food impaction and collection therein is also substantiallyreduced. In one embodiment, the base 24 is generally rectangular andnon-rotatable.

Base attachment fastener 28 is adapted for insertion into and engagementwith central opening 26 in base plate 24. In one embodiment, baseattachment fastener 28 is a bone screw.

Head 29 of base attachment fastener 28 has a central bore 32 formedlongitudinally in the body of fastener 28. In one embodiment, centralbore 32 of base attachment fastener 28 extends into threaded shaft 30.In one embodiment, head 29 of base attachment fastener 28 is acountersink head adapted to fit countersunk central opening 26.

Within this specification “jaw” 16 is intended and defined to includeeither the upper jaw or the lower jaw. Similarly, within thisspecification “bone” 14 is intended and defined to include either themaxilla or the mandible.

If base 24 is sized generally similarly to the bottom portion of aremoved tooth (not shown) then the periodontal gaps 12 on opposite sidesof the implanted crown portion 22 will not be enlarged. The base 24 maybe further enlarged to maximally minimize the periodontal gaps 12between the implant 20 and adjacent teeth 10.

In one embodiment of the invention, the base 24 has a sloping peripheralsidewall 25 and the bottom side portion is smaller in area than the topside portion. The bottom side portion of the base 24 may be embeddedwithin the bone 14 of the jaw 16. This may be done by removing a pieceof the patient's jawbone prior to adhering base 24 to the jawbone.Alternatively, if bone 14 strength is an issue, the bottom side portionof the base 24 may be generally fitted to the vertical curvature of thebone 14 of the jaw 16.

In another embodiment of the invention, the peripheral sidewall 25 ofthe base 24 is coated or roughened to facilitate gum 8 adhesion thereto.In one embodiment, the upper portion of the base attachment screw 28comprises an internally threaded hole, or central bore, 32 for receptionof a crown attachment bolt 34. It is also contemplated that the topportion of the base 24 and the bottom side portion of the crown 22 arematingly configured to ensure proper and non-rotatable alignment of thecrown portion 22 on the base 24.

FIG. 2 is a more detailed illustration of the base plate 24 and crownsupport mechanism 36 of implant 20. Tooth crown 38 is supported by andattached to crown supporting means 36. Together tooth crown 38, crownsupporting mechanism 36, and crown attachment screw 34 embody crownportion 22.

Base plate 24 has central opening 26 and coronal surface 27. The terms“coronal” and “apical” are used in this specification to describe theside of a structure closest to the crown apex (root), respectively, of atooth.

In one embodiment, central opening 26 of base plate 24 is countersunk.Central opening 26 may be beveled at any angle, even a concave angle, orit may be straight with no bevel. In one embodiment, coronal surface 27is a flat surface. In one embodiment, coronal surface 27 of base plate24 includes teeth means 44 for engagement, such as a plurality ofupstanding studs 44.

Crown supporting mechanism 36 carries crown attachment fastener 34.Crown supporting mechanism 36 is disposed on coronal surface 27 of baseplate 24. In one embodiment, crown support mechanism 36 includesrecessions 46 for engaging detents 44 (also referred to as upstandingstuds) of coronal surface 27. Of course, it will be appreciated that therecessions and detents may be on opposite parts or intermixed betweenthe two parts.

In one embodiment, crown support mechanism 36 includes a collar 40 (alsoreferred to as an abutment collar) and a cylindrical insert 42. Collar40 is shown partially cut away in FIG. 2. Collar 40 includeslongitudinal opening 48 with coronal 50 and apical 52 edges. Collar 40is disposed on coronal surface 27 of base plate 24.

Cylindrical insert 42 is disposed within collar 40 and supported bycoronal edge 50 of collar 40. Cylindrical insert 42 has a longitudinalchannel 58 formed therein for carrying crown attachment fastener 34.

Crown attachment fastener 34 is adapted for threaded engagement withcentral bore 32 of base attachment fastener 28. In one embodiment, crownattachment fastener 34 has a threaded shaft 56 adapted for threadedengagement with central bore 32.

It will also be appreciated that any one of a variety of commerciallyavailable prosthesis may be coupled to implant 30 as is known in theart. As such, the invention is not limited to a specific crownattachment fastener, collar abutment, or prosthesis. Rather, embodimentsof the invention provide a way to stabilize the implant screw andprosthesis using a stabile base or platform that is secured to the bone.

Generally, the method of implanting a tooth implant or prosthesis 20 ina jaw 16 comprises the following steps that do not necessarily need toproceed in order. The method utilizes a tooth implant 20, such as theone generally described above. A pilot hole 6 is drilled in the jawboneand is sized to accommodate the internal diameter of the base attachmentscrew 28. The hole 6 is laterally centered in the jaw 16 betweenadjacent teeth 10 in a open space left by a removed tooth (not shown).Sufficient gum 8 is removed to allow the base 24 to seat directly on thebone 14 of the jaw 16. Optionally, a portion of the jawbone may beremoved so that base 24 may sit within the jawbone and be flush with thetop surface. Once the treatment site is surgically prepared, thethreaded end portion 30 of the base attachment screw 28 is positionedthrough the upright opening 26 in the base 24 and screw 28 is screwedinto the bone 14 of the jaw 16 thereby attaching the base 24 to the jaw16. As described hereinafter, base 24 may first be secured to thepatient's jawbone by using one or more smaller screws that extendthrough the base and into the jawbone. These may be located, forexample, between the central opening of base 24 and its outer perimeter.With base 24 secured and screw 28 in place, the surgeon may position,fit and maintain the removed gum 8 peripherally around the base 24 thatis now attached to the jaw 16. A crown portion 22 may be molded and mayhave a bottom portion sized to fit on the base 24 and a top portionsized appropriately to fill the open space between the adjacent teeth10. The molded crown portion 22 may be attached to the base 24 that isanchored on the jaw 16. The base 24 of the implant 20 is enlarged tobetter distribute load on the jaw 16, so that periodontal gaps 12between the bottom portion of the crown portion 22 and adjacent teeth 10are thereby reduced, and so that both food impaction and collectiontherein is minimal. This most general method may be detailed with theapparatus limitations specified above under the most general descriptionof the tooth implant 20.

FIGS. 3-7 illustrate an embodiment for installing a tooth implant in ajaw 16 having bone 15 and gum 8. Although the steps represented in FIGS.3-7 are presented in a specific order, the technology presented hereincan be performed in any variation of this order. Furthermore, additionalsteps may be executed between the steps illustrated in FIGS. 3-7.

FIGS. 3 and 4 are side elevations of base plate 24 being fastened to jaw16. FIG. 5 is a top elevation of the step shown in FIG. 4. In oneembodiment, fastening base plate 24 to jaw 16 includes drilling a pilothole 6, removing gum 8 and or bone 14 from jaw 16, and positioningthreaded shaft 30 of base attachment screw 28 through central opening26. Typically, enough bone may be removed so that the top surface ofbase plate 24 is flush with the top of bone 14. Although not shown, baseplate 24 may include one or more through holes through which smallsurgical screws may be used to secure base plate 24 to bone 14. This maybe done prior to or after inserting attachment screw 28.

Pilot hole 6 is typically sized to accommodate the internal diameter ofbase attachment screw 28. Pilot hole 6 is laterally centered in jaw 16.Also, sufficient gum 8 is removed from jaw 16 to allow base plate 24 ofimplant 20 to seat directly on bone 14 of jaw 16 (in cases where no boneis removed). Threaded shaft 30 of base attachment screw 28 ispositioning through central opening 26 in base 24 of implant 20. Screw28 is screwed into bone 14 of jaw 16 thereby attaching base plate 24 tojaw 16.

FIG. 6 is a side elevation showing collar 40 being affixed to base plate24. Longitudinal opening 48 is provided in collar 40. Collar 40 isdisposed on coronal surface 27 of base plate 24. Crown attachmentfastener 34 is inserted through collar 40. Cylindrical insert 42 isdisposed within collar 40. FIG. 7 is a side elevation showing toothcrown 38 being attaching to collar 40.

Referring now to FIGS. 8 and 9, one exemplary embodiment of a base 110will be described. Base 110 is constructed of a stable material, such aspolished titanium, ceramics, zirconia, or the like. Base 110 has agenerally flat top surface 112 and a bottom surface 114. Base 110 alsohas four outer edges or sides 116, 118, 120 and 122. Formed in thecenter of base 110 is a central opening 124 through which an implant isinserted. Central opening 124 is beveled or tapered so that it generallymatches the shape of the head of the implant. This tapering also assiststo provide microleakage between base 110 and the implant.

Base 110 is generally square or rectangular in geometry and may haverounded corners. Typically, the length of sides 116 and 120 will be inthe range of about 7 mm to about 12 mm, and more typically from about 8mm to about 12 mm. The length of the opposing sides 118 and 122 may bein the range from about 5 mm to about 10 mm, and more particularly fromabout 6 mm to about 9 mm. The thickness of base 110 between top 112 andbottom 114 will typically be about 1 mm to about 4 mm, and moretypically from about 2 mm to about 3 mm. Also, sides 116, 118, 120 and122 may be angled from top 112 to bottom 114. Such angling of the sidesis particularly useful for directing chewing force into the platform andbone and transferring it to the center implant to evenly disperse theload. Also, the sides and bottom 114 may be roughened to facilitate boneintegration. For example, a pressure blasted aluminum oxide microetching process may be used. Other processes include acid etching orother techniques to increase the surface area of the sides and thebottom. Also, grooves 130 may be placed on the sides of base 110 to alsoincrease surface area and facilitate bone integration.

Also extending through base 110 are a pair of screw holes 132 and 134.These screw holes are also beveled or tapered to permit small surgicalscrews to be inserted through these holes and be flush with the topsurface 112. These small screws extend into the patient's jawbone andserve to secure base 110 to the patient's jawbone. As shown, base 110includes two screw holes which are located at opposing corners of thebase. However, it will be appreciated that different numbers of screwholes could be used. For example, base 110 could be constructed withonly a single screw hole. Alternatively, it could employ three screwholes, with two being in adjacent corners and one being on the oppositeside. As another option, four screw holes could be employed, with thefour holes being located in each of the corners. In still a furtheroptions, base 110 may not include any such screw holes, relying on boneadhesion to secure base 110 within the patient's jawbone.

Base 110 also includes two detents or dimples 138 and 140 in top surface112. These dimples are designed to receive mating features on theabutment to prevent rotational movement of the abutment relative to base110 once the abutment is secured to the implant. Although shown withdimples, it will be appreciated that other types of non-rotationalfeatures may be used. For example, bumps or ridges could be included ontop surface 112 to mate with detents or dimples on the abutment. Also,any number of such non-rotational features could be employed.

FIG. 10 illustrates a cross-sectional view of a patient's jawbone priorto placement of base 110 or an implant. In FIG. 10, the patient'sjawbone is illustrated by reference numeral 142 and the tissue or gumline above the patient's jawbone is illustrate by reference numeral 144.As shown, one tooth has been removed leaving a space or void betweenadjacent teeth 146. Prior to placement of an implant or a base, anappropriate hole 148 is drilled and a generally square or rectangularrecess 150 is cut into the patient's jawbone. As illustrated in FIG. 11,base 110 has been secured within recess 150. The sides 116, 118, 120 and122 generally match with the outer sides or walls of recess 150 whilebottom 114 rests upon the removed portion of the jawbone. To secure base110 in place, screws 151 have been inserted through screw holes 132 and134 (see FIG. 8) and into the jawbone. Screws 151 will typically have alength in the range from about 5 mm to about 11 mm, and more typicallyfrom about 7 mm to about 9 mm. In this way, base 110 is secured to thepatient's jawbone 142. Top surface 112 is generally flush with the topof the patient's jawbone so that it essentially functions as part of thepatient's jawbone. A more detailed view of screws 151 that secure base110 to the patient's jawbone is illustrated in FIG. 12.

Once base 110 is securely in place, an implant 152 is screwed into theopening 148 until the head of the implant is seated within centralopening 124. At this point, a screw or healing cap may be inserted intothe top end of implant 152 and remain in place for several weeks untilbone has properly healed and adhered to base 110. The healing cap maythen be removed so that an abutment 154 (see FIG. 11) may be secured tobase 110. For example, a hex 156 may be screwed through a centralopening of abutment 154 and into implant 152. Also, bumps 160 on theundersurface of implant 154 mate with detents 138 and 140 on base 110 toprevent rotational movement of abutment 154 relative to base 110. Onceabutment 154 is securely in place a prosthesis, such as a crown, issecured to abutment 154. The outer shape of abutment 154 is generallysquare or rectangular in geometry and therefore matches the outer shapeof base 110. In this way, voids or gaps between the crown that is placedon abutment 154 and the adjacent teeth 146 is minimized. Typically, theouter edges of abutment 154 will come within about 1 mm to about 4 mm ofside walls 116, 118, 120 and 122. This provides sufficient space for theresulting crown that will be placed on top of abutment 154.

FIG. 13 is a perspective view of a template 200 that may be used whensurgically producing the sites needed for placement of an implant andbase as described in previous embodiments. Template 200 is molded sothat it fits over the patient's teeth. Also, template 200 has twothrough holes 202 and 204 that serve as guides when removing thepatient's jawbone at a treatment site. Although shown with two throughholes, it will be appreciated that any number may be used depending onthe number of implant sites. Through holes 202 and 204 are specificallyaligned with where the patient's removed teeth were previously located.In this way, when a surgical device, such as a hand-held router, isdirected through the through holes 202 and 204, it produces arectangular recess in the patient's jawbone.

FIG. 14 illustrates the recesses 206 and 208 that are formed within thepatient's jawbone when using template 200 of FIG. 13. Also shown are twoholes 210 and 212 that have been drilled to receive the implant. Aboveholes 210 and 212 are the rectangular recesses 206 and 208 in thejawbone which are sized to receive bases or platforms as describedherein.

FIG. 15 illustrates in phantom line the implants 152, bases 110 andsurgical screws 151 previously described in connection with FIG. 11.Also positioned on top of each base is a crown 214 and 216. Not shown inphantom line for convenience of illustration are the abutments that sitbetween the crowns and the base. As shown, the space between each crownand/or adjacent tooth is minimized by the nature of the rectangularbases. In this way, the amount of food or other material that may bepotentially trapped between two adjacent teeth and/or crowns isminimized.

FIGS. 16-19 illustrate another embodiment of a dental implant system300. System 300 includes a base member 302, sometimes also referred toas a platform. Base member 302 has a flat top side 304, a bottom side306 and an outer periphery 308. Similar to other embodiments describedherein, outer periphery 308 is a generally rectangular in geometry withrounded corners. The outer periphery may be sized to generally match thesize of the crown that is to be placed onto base member 302. Forinstance, in the example illustrated hereinafter, base member 302 mayhave a length (in a direction aligned with the jawbone) that is therange from about 7 mm to about 12 mm, and more particularly about 9 mmand a width (generally perpendicular to the length of the jawbone) inthe range from about 5 mm to about 10 mm, and more particularly about 7mm. The depth of base member 302 as measured from top side 304 to bottomside 306 may be in the range from about 1 mm to about 4 mm, and moreparticularly about 2.5 mm. Other shapes and sizes are possible,particularly depending on the size and the shape of the tooth for whichit is replacing. Merely by way of example, base member 302 may becircular, oval, square, octagonal, hexagonal, or even custom shaped tothe shape of a tooth. All or only a portion of the sides of base member302 may be tapered so that top side 304 is greater in surface area thanbottom side 306. In the example illustrated, approximately the top thirdof base member 302 has sides that are perpendicular to top side 304. Thebottom two-thirds of the side walls taper inward at an angle. The reasonfor tapering of the side walls is to facilitate placement of base member302 into a recessed region of the patient's jawbone. By tapering theside walls, a practitioner can more easily place the base member 302into the recess which may have a relatively tight fit.

Materials that may be used to construct base member 302 includetitanium, ceramics, zirconia, and the like. As with other embodimentsdescribed herein, the walls and bottom side 306 of base member 302 maybe roughened, coated or treated with a surface treatment to increase thesurface area of the base member in order to enhance bone growth orosseointegration.

Base member 302 further includes a central opening 312 that extendscompletely through the base member 302. Central opening 312 tapers fromtop side 304 to bottom side 306 to permit a cold weld to be formedbetween an implant screw 314 as described hereinafter. Base member 302further includes a pair of recesses 316 and 318. As best illustrated inFIG. 19, recesses 316 and 318 are positioned on the diagonal of top side304 and are cylindrical in geometry. Recesses 316 and 318 are eachdesigned to receive an alignment pin 320. These alignment pins are usedto align an abutment 322 on top side 304 of base member 302. Pins 320are also used to prevent abutment 322 from rotating relative to basemember 302. Pins 320 are press fit into recess 316 and 318, typically bya force applied by human fingers. Pins 320 are cylindrical in geometryand may be constructed of materials similar to those used for basemember 302. Also, a bottom end 322 of pins 320 may be chamfered tofacilitate introduction into recesses 316 and 318. Similar to otherembodiments, other alignment or anti-rotation mechanisms could also beused, including detents or other interlocking elements.

Although shown with two recesses and alignment pins, it will beappreciated that other numbers may be included, such as a single pin, ormore than two pins. Further, the recesses and pins may have other sizes,shapes and locations on base member 302. For example, the pins could besquare and located midway between two opposite sides of base member 302.

Implant screw 314 includes a threaded end 326, a head 328 and a taperedhead section 330. Extending through head 328 is a threaded opening 332(see FIG. 18). Threaded end 326 is configured to be screwed into thepatient's jawbone after passing through central opening 312 of basemember 302. Typically, implant screw 314 will have a length that extendswell below base member 302 so as to be fully implanted in the bone.Implant screw 314 may be constructed of a biocompatible material, suchas titanium. Tapered section 330 has a smooth outer surface thatdirectly contacts the surface of central opening 312. As torque isapplied to implant screw 314, a cold weld is formed between taperedsection 330 and base member 302 to prevent bacteria from travelling downinto the jawbone.

Threaded opening 332 is configured to receive a capture screw 340 thatsecures abutment 322 to base member 302. Capture screw 340 has an upperend 342 with a head 343 and a threaded lower end 344. Also, upper end342 includes a smooth shank 346.

Abutment 322 includes a bottom surface 350 and an upper surface 352. Athrough hole 354 extends through abutment 322 and includes a shoulder356 (see FIG. 18) that is configured to engage with head 343 of capturescrew 340 to securely seat implant 352 against top side 304 of basemember 302. Also, recess 323 and 325 are used to receive alignment pins320.

The lower portion of through hole 354 is configured to receive acylindrical locating sleeve 360. The inner surface of locating sleeve360 is configured to be placed about shank 346. Locating sleeve 360includes a top end 362 and a chamfered bottom end 364. Locating sleeve360 is configured to be placed into head 328 of implant screw 314,preferably by a press fit. To do so, head 328 includes a space 366located above threaded opening 332. Locating sleeve 360 not only servesto assist in aligning abutment 322 with base member 302, but also servesto mechanically secure these two parts together. In some cases, locatingsleeve 360 may be omitted, making this part optional. Space 366 is alsoused to receive a torquing instrument, such as an Allen's wrench, whentightening implant screw 214. As best shown in FIG. 19, space 366 can behexagonal in shape, although other geometries may be used. Locatingsleeve 360 is used to facilitate placement of abutment 322 onto basemember 302 and also the placement of capture screw 340 into threadedopening 332. In use, locating sleeve 360 is pressed through centralopening 312 and into space 366 of implant screw 314, with the chamfer onbottom end 364 facilitating its placement. Locating sleeve 360 isinserted into space 366 until resting on a shoulder 370. Abutment 322 isthen placed onto base member 302, with locating sleeve 360 extendinginto through hole 354, preferably with a press fit. Capture screw 340may then be inserted through through hole 354 where it passes throughlocating sleeve 360 and into opening 332.

Capture screw 340 may also include a hexagonal opening 380 in head 343that permits a wrench to apply a torque to capture screw 340. By turningcapture screw 340 into implant screw 314, bottom surface 350 of implant322 is forced against top side 304 of base member 302. Both top tide 304and bottom surface 350 are manufactured to be sufficiently smooth sothat no more than about 20 microns of space is between them when screw340 is tightened. In this way, a tight seal is provided between abutment322 and base member 302.

Referring now to FIGS. 20-28 one exemplary method for placing the dentalimplant system of FIGS. 16-19 will be described. FIG. 20 illustrates across section of a patient's jawbone 400 where a tooth has been removed,leaving an opening between teeth 402 and 404. Initially, tissue 406 isdissected, by laying open a flap of tissue, to expose bone 400 at asurgical site 408.

In FIG. 21, a section of bone 400 is removed to form a recess 410. Bone400 may be removed in a variety of ways, including by use of a router, adrill, or the like. Recess 410 preferably is formed to have the samesize, shape and depth of the base member so that minimal bone growthwill be required in order to fully secure the base member to bone 400.Base member 302 is then placed within recess 410 such that top side 304is generally flush with the top of bone 400, just below the gum line. Inthis way, as base member 302 becomes integrated within bone 400 it takesthe same overall shape as the bone before surgery. With proper boneintegration, additional securing screws may not be needed to hold basemember 302 within recess 410, thereby providing a smoother surfacebetween top side 304 and bottom surface 350 of abutment 322.

As shown in FIG. 23, after base member 302 is in place, a hole isdrilled into bone 400 using a drill bit 420 which is passed throughcentral opening 312 of base member 302. Progressively larger drill bitswith increasing diameters may be used until the opening in bone 400 islarge enough to receive the implant screw. For example, threeprogressively larger drill bits may be used to form the hole in bone400. As shown in FIG. 24, implant screw 314 is then inserted throughcentral opening 312 and into the opening in bone 400. Implant screw 314is tightened until tapered head section 330 is fully seated withincentral opening 312. A force of around 35 Ncm may be applied with atorque wrench to fully seat implant screw 314 and form a seal thatprevents liquids or bacterial from seeping through central opening 312.

As shown in FIG. 25, a healing cover 430 is screwed into opening 332 ofimplant screw 314. Healing cover 430 is a low profile cover having amaximum height of about 2 mm that extends to the outer periphery of topside 304. Tissue 406 is sutured over cover 430 and left in place forabout 3 months while the surgical site heals. When healing is complete,bone integration with base member 302 has occurred and tissue 406 isremoved to expose cover 430 which is then removed from base member 302.

A tissue contouring cap 432 (see FIG. 26) is secured to implant screw314 and base member 302 to form the tissue at the surgical site so thatit will be ready to receive the abutment. Tissue contouring cap 432 maybe left in place for about 2 weeks, then removed.

Following removal of tissue contouring cap 432, abutment 322 is placedonto base member 302 as shown in FIG. 27. To do so, locating sleeve 360may be inserted into space 366 and forced into place. Also, alignmentpins may be placed into the recess 316 and 318 of base member 302.Abutment is moved toward top side 304, with locating sleeve 360extending into through hole 354 and pins 320 passing into recesses 323and 325. Capture screw 340 is inserted through through hole 354 and intoopening 332 of implant screw 314. A torque wrench is used to tightencapture screw 340, typically with a force of about 25 Ncm to form atight seal between abutment 322 and base member 302.

With implant 322 in place, an impression of the crown is made. As shownin FIG. 28, a crown 450 is cemented onto abutment 322.

In many cases, the top of a person's jawbone will not be flat or planar,particularly after a tooth has been removed. For example, the jawboneand/or recess from the removed tooth may taper downward in a directionfrom lingual to buccal (as shown, for example, in FIG. 31) or buccal tolingual, or from back to front or front to back. In such cases, someembodiments of the invention provide a platform or base member that hasa top surface that is angled or otherwise shaped to match the profile ofthe top of the jawbone after being inserted into the patient's jawbone.The abutment that is used in combination with the base member may have abottom surface with a corresponding shape so that when the crown isplaced atop the abutment, it will be generally aligned with thepatient's other teeth.

One such embodiment of a dental implant system 500 is illustrated inFIGS. 29 and 30. System 500 includes a base member 502, also referred toas a platform. Base member 502 has a flat top side 504, a bottom side506 and an outer periphery 508. Similar to other embodiments describedherein, outer periphery 508 is a generally rectangular in geometry withrounded corners and may have similar outer dimensions. For example, theouter periphery may be sized to generally match the size of the crownthat is to be placed onto base member 502.

One important feature of base member 502 is that top side 504 is angledrelative to bottom side 506. This angle may be in the range from about 5degrees to about 20 degrees, although other angles could be used insevere cases. The angle may also depend on size and shape of the removedtooth, as well as the size and shape of the jawbone and associatedrecess. In some cases, the difference in the height of base member 502as measured from top side 504 to bottom side 506 may vary from about 1mm to about 8 mm at one side to about 4 mm to about 15 mm at theopposite side. Further, although described as being rectangular, othershapes are possible. For example, base member 502 may be circular, oval,square, octagonal, hexagonal, or even custom shaped to the shape of atooth. Further, as with other embodiments, the top side does notnecessarily need to be flat or planar, especially in cases where basemember 502 is customized for a particular application. All or only aportion of the sides of base member 502 may be tapered so that top side504 is greater in surface area than bottom side 506. The reason fortapering of the side walls is to facilitate placement of base member 502into a recessed region of the patient's jawbone. By tapering the sidewalls, a practitioner can more easily place the base member 502 into therecess which may have a relatively tight fit.

Materials that may be used to construct base member 502 include any ofthose described herein. Also, the walls and bottom side 506 of basemember 502 may be roughened, coated or treated with a surface treatmentto enhance bone growth or osseointegration as with other embodiments.

Base member 502 further includes a central opening 512 (see FIGS. 35 and39) that extends completely through the base member 502. Central opening512 tapers from top side 504 to bottom side 506 to permit a cold weld tobe formed between an implant screw 514. Base member 502 may optionallyinclude a pair of recesses 516 and 518. Recesses 516 and 518 may bepositioned on the diagonal of top side 504 and may be cylindrical ingeometry. Recesses 516 and 518 are each designed to receive an alignmentpin 520. These alignment pins are used to align an abutment 522 on topside 504 of base member 502. Pins 520 are also used to prevent abutment522 from rotating relative to base member 502. Pins 520 are press fitinto recess 516 and 518, typically by a force applied by human fingers.Pins 520 may be cylindrical in geometry and may be constructed ofmaterials similar to those used for base member 502. Also, a bottom end522 of pins 520 may be chamfered to facilitate introduction intorecesses 516 and 518. Similar to other embodiments, other alignment oranti-rotation mechanisms could also be used, including detents or otherinterlocking elements.

Further, although shown with two recesses and alignment pins, it will beappreciated that other numbers may be included, such as a single pin, ormore than two pins. Further, the recesses and pins may have other sizes,shapes and locations on base member 502. For example, the pins could besquare and located midway between two opposite sides of base member 502.Further, it will be appreciated that in some cases, the use of alignmentand/or anti-rotation pins or features may not be needed.

Implant screw 514 includes a threaded end 526, a head 528 and a taperedhead section 530. Extending through head 528 is a threaded opening 532(see FIG. 39). Threaded end 526 is configured to be screwed into thepatient's jawbone after passing through central opening 512 of basemember 502. Typically, implant screw 514 will have a length that extendswell below base member 502 so as to be fully implanted in the bone.Implant screw 514 may be constructed of a biocompatible material, suchas titanium. Tapered section 530 has a smooth outer surface thatdirectly contacts the surface of central opening 512. As torque isapplied to implant screw 514, a cold weld is formed between taperedsection 530 and base member 502 to prevent bacteria from travelling downinto the jawbone.

Threaded opening 532 is configured to receive a capture screw 540 thatsecures abutment 522 to base member 502. Capture screw 540 has an upperend 542 with a head 543 and a threaded lower end 544. Also, upper end542 includes a smooth shank 546.

Abutment 522 includes a bottom surface 550 and an upper surface 552. Athrough hole 554 extends through abutment 522 and includes a shoulder556 (see FIG. 39) that is configured to engage with head 543 of capturescrew 540 to securely seat implant 552 against top side 504 of basemember 502. Also, recesses 523 and 525 are used to receive alignmentpins 520.

Bottom surface 550 may be generally flat or planar in geometry, althoughother shapes are possible. Bottom surface 550 is angled relative toupper surface 552, typically at the same angle of incline as that of topside 504 on abutment 502 relative to bottom side 506. This permits thecrown that is placed onto abutment 502 to be generally flush or alignedwith the adjacent teeth. However, it will be appreciated that differentangles of inclination may be used depending on the geometry needed toalign the crown with the adjacent teeth.

The lower portion of through hole 554 is configured to receive acylindrical locating member or sleeve 560. It will be appreciated, thatthis sleeve or locating member is optional and may not be used in someembodiments. Further, shapes other than cylindrical may be used, such ashexagonal. The inner surface of locating sleeve 560 is configured to beplaced about shank 546. Locating sleeve 560 includes a top end 562 and achamfered bottom end 564. Locating sleeve 560 is configured to be placedinto head 528 of implant screw 514, preferably by a press fit. To do so,head 528 includes a space located above threaded opening 532. Locatingsleeve 560 not only serves to assist in aligning abutment 522 with basemember 502, but also serves to mechanically secure these two partstogether. As previously described, in some cases, locating sleeve 560may be omitted, making this part optional. A torquing instrument, suchas an Allen's wrench, may be used to tighten implant screw 514 similarto other embodiments.

In use, locating sleeve 560 is pressed through central opening 512 andinto space 566 of implant screw 514. Locating sleeve 560 is insertedinto space 566 until resting on a shoulder 570. Abutment 522 is thenplaced onto base member 502, with locating sleeve 560 extending intothrough hole 554, preferably with a press fit. Capture screw 540 maythen be inserted through through hole 554 where it passes throughlocating sleeve 560 and into opening 532.

Capture screw 540 may also include a hexagonal or other shaped opening580 in head 543 that permits a wrench to apply a torque to capture screw540. By turning capture screw 540 into implant screw 514, bottom surface550 of implant 522 is forced against top side 504 of base member 502.Both top side 504 and bottom surface 550 are manufactured to besufficiently smooth so that no more than about 20 microns of space isbetween them when screw 540 is tightened. In this way, a tight seal isprovided between abutment 522 and base member 502. Also, because bothtop side 504 and bottom surface 550 are constructed with complementaryangles of inclination, abutment 522 is held upright in the patient'sjaw. At the same time, base member 502 serves to fill in the space ofthe missing jawbone to provide the necessary structure to hold theabutment and crown.

Although shown as two separate components, it will be appreciated thatin some cases the abutment and base member may be constructed as asingle integral unit. One example will be described hereinafter withreference to FIGS. 41 and 42.

Referring now to FIGS. 31-40 one exemplary method for placing the dentalimplant system of FIGS. 29 and 30 will be described. FIG. 32 illustratesa cross section of a patient's jawbone 600 where a tooth has beenremoved, leaving an opening 601 between teeth 602 and 604. Jawbone 600tapers from lingual 610 to buccal 612 as shown in FIG. 31. Initially,tissue 606 is dissected, by laying open a flap of tissue, to expose bone600 at a surgical site 608.

In FIG. 33, a section of bone 600 is removed to form a recess 616. Bone600 may be removed in a variety of ways, including by use of a router, adrill, or the like. Recess 616 preferably is formed to have the samesize, shape and depth of the base member so that minimal bone growthwill be required in order to fully secure the base member to bone 600.As shown, the top surface of bone 600 is angled downward and willgenerally match the angle of top side 504 of base member 502. As shownin FIG. 34, base member 502 is then placed within recess 616 such thattop side 504 is generally flush with the top of bone 600, just below thegum line. In this way, as base member 602 becomes integrated within bone600 it takes the same overall shape as the bone before surgery. Withproper bone integration, additional securing screws may not be needed tohold base member 502 within recess 616, thereby providing a smoothersurface between top side 504 and bottom surface 550 of abutment 522. Aspreviously described, the angling of top side 504 facilitates thisprocess.

As shown in FIG. 35, after base member 502 is in place, a hole isdrilled into bone 600 using a drill bit 620 which is passed throughcentral opening 512 of base member 502. Progressively larger drill bitswith increasing diameters may be used until the opening in bone 600 islarge enough to receive the implant screw. For example, threeprogressively larger drill bits may be used to form the hole in bone600. As shown in FIG. 36, implant screw 514 is then inserted throughcentral opening 512 and into the opening in bone 600. Implant screw 514is tightened until tapered head section 530 is fully seated withincentral opening 512 to form a seal that prevents liquids or bacterialfrom seeping through central opening 512.

As shown in FIG. 37, a healing cover 630 is screwed into opening 532 ofimplant screw 514. Healing cover 630 is a low profile cover having amaximum height of about 2 mm that extends to the outer periphery of topside 504. Healing cover 630 may also include an angled lower surfacesimilar to that on abutment 522. Tissue 606 is sutured over cover 630and left in place for about 3 months while the surgical site heals. Whenhealing is complete, bone integration with base member 502 has occurredand tissue 606 is removed to expose cover 630 which is then removed frombase member 502.

A tissue contouring cap 632 (see FIG. 38) is secured to implant screw514 and base member 502 to form the tissue at the surgical site so thatit will be ready to receive the abutment. Tissue contouring cap 632 maybe left in place for about 2 weeks, then removed. Also, contouring cap632 may have a bottom surface that is angled similar to abutment 522.

Following removal of tissue contouring cap 632, abutment 522 is placedonto base member 502 as shown in FIG. 39. To do so, locating sleeve 560may be inserted into space 566 and forced into place. Also, alignmentpins may be placed into the recess 516 and 518 of base member 502.Abutment is moved toward top side 504, with locating sleeve 560extending into through hole 554 and pins 520 passing into recesses 523and 525. Capture screw 540 is inserted through through hole 554 and intoopening 532 of implant screw 514. A torque wrench is used to tightencapture screw 350 to form a tight seal between abutment 522 and basemember 502.

As shown, the angling of the top side 504 of base member 502 and thebottom surface 550 of abutment 522 permits abutment 522 to be fullyupright and aligned with adjacent teeth. Further, base member 502provides additional support where portions of the jawbone are missing sothat abutment 522 is more secured within the jawbone.

With implant 522 in place, an impression of the crown is made. As shownin FIG. 40, a crown 650 is cemented onto abutment 522.

FIGS. 41 and 42 illustrate another embodiment of a dental implant system700. System 700 has an integrated base member/abutment 702 that may beconstructed as a single integral unit. Base member/abutment 702 has acentral opening 704 that is employed to receive an implant screw 706that extends through base member/abutment 702. Opening 704 mayoptionally be tapered, and the head of implant screw 706 may also betapered to provide a tight seal.

In use, bone may be removed in bone 720 similar to other embodiments andbase member/abutment 702 set in place. A hole may then be drilled intobone 702 and implant screw 706 screwed into bone 702. Steps described inconnection with other embodiments may also be used in connection withsystem 700.

The foregoing description is only illustrative of the invention and notintended to be exhaustive or to limit the invention to the precise formsdisclosed. Various alternatives and modifications can be devised bythose skilled in the art without departing from the invention.Accordingly, the present invention embraces all such alternatives,modifications, and variances that fall within the scope of the appendedclaims.

What is claimed is:
 1. A dental implant system comprising: a base memberthat is adapted to be embedded within a patient's jawbone at a treatmentsite, wherein the base member has a generally flat top defining an outerperiphery, a buccal side, a lingual side, a bottom, and a centralopening, wherein the base member is configured to be positioned within arecess in the patient's jawbone, and wherein one of the lingual side andthe buccal side is longer than the other; an implant screw comprising ahead and a threaded end, wherein the threaded end is adapted to passthrough the central opening of the base member and into the patient'sjawbone, and wherein the head is adapted to be seated within the centralopening of the base member after the threaded end is screwed into thepatient's jawbone, wherein the implant screw defines a threaded openingin the head; and an abutment that is configured to be placed onto thetop of the base member, wherein the abutment comprises: a bottom surfacethat is configured to be positioned adjacent the base member, a shapedupper surface that is adapted to receive a crown; a through holeextending longitudinally through the abutment; a locating member that isadapted to extend from the through hole of the abutment and into thehead of the implant screw; at least one alignment feature that isconfigured to align the base member with the abutment; and a capturescrew that is configured to be inserted through the through hole of theabutment, through the locating member and into the threaded opening inthe head of the implant screw.
 2. A dental implant system comprising: abase member that is adapted to be embedded within a patient's jawbone ata treatment site, wherein the base member has a generally flat topdefining an outer periphery, a buccal side, a lingual side, a bottom,and a central opening, wherein the base member is configured to bepositioned within a recess in the patient's jawbone, and wherein one ofthe lingual side and the buccal side is longer than the other; animplant screw comprising a head and a threaded end, wherein the threadedend is adapted to pass through the central opening of the base memberand into the patient's jawbone, and wherein the head is adapted to beseated within the central opening of the base member after the threadedend is screwed into the patient's jawbone, wherein the implant screwdefines a threaded opening in the head; and an abutment that isconfigured to be placed onto the top of the base member, wherein theabutment comprises: a bottom surface that is configured to be positionedadjacent the base member, and a shaped upper surface that is adapted toreceive a crown; wherein the base member defines at least one recess inthe top, wherein the bottom of the abutment defines at least one recessthat is aligned with the recess in the base member when the abutment isplaced onto the base member, wherein the alignment feature comprises apin that is configured to fit within the recess of the base member andthe abutment, wherein the abutment and the base member each includeanother recess that are aligned with each other when the abutment isplaced onto the base member, and further comprising another alignmentpin that is adapted to fit within the recesses.